Method and apparatus for concentrating ore.



H. IVI. DUNN.

METHOD AND APPARATUS FOR CONCENTRATING ORE.

APPLICATION FILED MAY Il. 1915.

Patented Mar. 13, 1917.

UNiTED STATES PATENT OFFICE."

HARRY' 1a. DUNN,v or HURLEY, NEW MEXICO.'A

METHOD AND APPARATUS ron ooNcENTRATING 03E.

T0 all whom it may concern.'

Be it known that I, HARRY M. DUNN, a citizen of the United States, and a residen-t of Hurley, in the county of Grant, in the State of New Mexico, have invented new and useful Improvements in Methods and Apparatus for Concentrating Ore, of whichl the following is such a full, clear, and concise disclosure as will enable others skilled in the art to which this invention relates to make and use the same.

My invention relates to the concentration j of ore andparticularly to that type 'of concentration commonly known as ore flotation.

It is now well known that if finely divided ore is mixed with water to forln a pulp and oil, tar or grease is added to this mixture and it is agitated so that air is thoroughly mixed through the complete mixture and comes in contact with the ore particles the oil, tar or grease assists the metalliferous particles of the ore to hold to them some of the air and the metalliferous particles are floated to the surface of the mixture while the particles of the gangue do not hold any of the air to them and they sink tothe bottom and are sepa-rated. The metalliferous particles are brought to the surface in aI Vthe presence of oil, tar or grease, any of which will hereinafter be termed oil, when the ore is mixed with or held in suspension in water. To this end I set in motion a mixture of water andinely divided ore, said mixture preferably including a relatively small quantity of oil, by subjecting said mixture to the action of a 4jet of gas, then using the energy thus imparted to the mixture to elevate the mixture, andthen permitting 1t to fall back upon itself or another portiony of the mixture whereby the-mixture is agitated and the air is brought into contact with the'particles of the metalliferous constituents of the ore and adhering to themH it carries them to the surface. i

Specification of Letters Patent.

`jector oil :is fed to it.

Another object of my invention is to provide an apparatus for bringing gas into intimate contact with particles of finely divided ore preferably in the presence of oil, when the finely divided ore is mixed with or held in suspension in water. To this end I provide means for projecting a mixture of finely divided ore and water, said mixture preferably including a small percentage of oil, against a throwback plate, said plate being preferably inclosed in a chamber, whereby said mixture falls back upon itself preferably to be thrown again against the throwback plate whereby a rolling motion-is imparted to the mixture` lThe means for projecting the mixture against the throwback plate is preferably a. gas operated injector. Gas is thus introduced into the mixture and the rolling motion thereof brings it into intimate contact with the oil-coated metalliferous particles of the ore. The metalliferous particles thus hold air to them and they are floated to the surface as a froth.

vIn addition to a device for bringing the gas into contact with the particles of the ore,

said particles preferably being treated with oil, I provide a chamber or spitzkasten in which the mixture is brought to rest in order that the gas may bring the particles of the metalliferous constituents to the surface Aof the mixture as a froth and also a receptacle or launder into which the froth is deposited preparatory to freeing it of oil.

In the device hereinafter described as embodying my invention and carrying out my process the mixture is projected into the chamber containing the throwback plate and against said plate by an air operated injector which draws the mixture into it from the lower part of the chamber or spitzkasten andas the mixture passes through the in- I do not, however, intend that my invention shall be limited to this means of projecting the mixture against means for causing the mixture to fall back j upon 'itself to agitate it, for I intend that my invention shall be defined by the hereunto appended claims.

Other and further advantages and objects Patented Mar. 13, 1917. Application filed May 11, 1915. Serial No. 27,348. I i

will appear from the following'description taken in connection with the accompanying drawings formmg. appart of this specification and be pointed out in the claims.

Inthe accompanying' drawings in which like reference characters indicate like parts Figure 1 is a view of a series of cells, partly broken away, which embody my invention; Fig. 2 is a perspective sectional view taken 5 on the line 2-2`of Fig. 1; Fig. 3 is a,sec h tional detail view of the oil spraying nozzle; and Fig. 4 is a sectional view of a modified form of a gasilijector.

In concentrating ore according to the process embodying my invention the ore is finely divided and mixed with water which holds it in suspension forming what is commonly known as pulp. This pulp is fed from a mixer by a trough 1 into a tank 2 which converges toward its bottom and in which the pulpthickens. It is fed through a spigot 3 into a riser l of a feed conduit 5 from which it passes through the opening 6 into thespitzkasten or chamber A of the first cell 7. The succeeding cells S and 9 are similar to the cell 7, each having a chamber A and the treatment of the pulp while in each chamber will later be stated in connectionwith a description of a single cell. The chamber Asof each cell communicates with the chamber A of each succeeding cell through an opening 10 and the last cell opens into a tailings trough 11 through a similaropening 10. The flow through the openings 10'is impeded by a. partition 12 in each cell, and the flow through the opening 6 and the openings 10 is restricted so as to preserve a correct level of liquid Vin ^each cell by a gate 13 operated in any well known manner by a hand-wheel 14. A

Adjacentto 'each chamber or spitzkasten A is a mixing or agitating chamber B separated from chamber A by a wall 15. Through this wall 15 extends one leg 17 of 40 each of two substantially L-shaped pipe sections 17, the other leg 17" of 'which extends toward the bottom of chamber A. Through the wall of each pipe section 17 extends a gas pipe 1 6 positioned axially of thedeg 17 l and extending across the opening whereby the leg 17 communicates with the leg 17` O11, grease or tarv is fed through a pipe 1S, preferably under pressure, whereby it is atomized by the nozzle 19, but in the modil fication shown in Fig. 4 it need not be under great pressure as the oil which is supplied through the usual pipe 16 is conducted in through the side of the leg 17 of the pipe section 17 by means of the pipe-end 119 so that it isfed directly into the pulp as it enters the leg 17 Pulp enters one. side of the chamber or spitzkasten A andv as gas is forced in to the gas pipe 16 it receives acharge of oil 'i 60 in the form of a spray from the nozzle 19,

and as Ithe air so charged passes out of leg 17 lpulp is carried in to the le 17 by the entraimng action. of the air. he pulp is thus preliminary mixed with the gas and ab olland it has limparted to it a, considerable `is a downward flow along the wall 15 and velocity by the action of the gas. It is projected substantially horizontally against the vertically curved throwback plate 20 whereby it is elevated and falls back upon itself. As the chamber B fills up there is a stream of the complete mixture rising along the surface of the plate 20, and the stream from the leg 17 entrains some of the mixture and carries it into the rising stream so that there 75 the whole mass has a rolling motion as 1ndicated b v the arrows as, This rolling motion-is thus due to a rising of one portion of themass and permitting the rising part to fall back upon itself and upon the remainder of the mass and an entrainingof a part of the otherwise stationary mass and I have found this rolling motion extremely efficient in* bringing the gas into intimate contact with' the oil-coated particles of the 85 metalliferous constituents of the ore.

As the level of the mixture rises in the chamber B the larger bubbles will throw the lighter froth which forms over the wall 15 and it will pass down between the wall 15 n and the curtain 21 onto the top of the mass of pulp in the chamber A which rises approximately to the level of the lower edge of the curtain 21Ito form a seal, at least when the froth forms on the top of the pulp. ,The level of the froth continues to rise as the mixer operates and the froth is drawn off over the lip K into the launder L which extends across the front of each cell. The launders discharge into. one another as indicated in Fig. 1 and then into the ore bin 22 in which the froth is collectedand the oil is later separated from the matalliferous particles. l

v It will be seen that the pulp is fed into the bottom of each chamber A and retarded from passing out therefrom by the partition 12 until it has been projected into the chamber B so that it is the pulp which has been thrown overv the top of the wall 15 which passes over the top of the partition 12 and into the next chamber A of the next cell. It will be seen, therefore, that what particles yof the metalliferous constituents of the ore are not floated in one cell will be acted on in the next cell and floated therein. It will be seen from the structure thus.v described that'the pulp, enters thefirst cell through "the openingy 6.y It is then ejectedy from the #chamber A by the gas operated injectors and that my invention shall'be defined by' do not intend that my invention shall be limited -to the features herein disclosedbut intend that modifications thereof may be made which occur to those skilled in the art the hereunto appended claims only.

IVhat I claim and desire to secure by Letters Patent of the United States is the following:

1. The herein described method of concentrating ores which consists in imparting an upward velocity in substantially vertical planes only to a stream of a mixture of pulp and a fiothing agent, permitting the eievated portion of the stream to fall back upon itself in contact with a free atmosphere whereby air is entrained in the mixture. and separating the 'froth `produced l thereby.

2. The herein described method of concentrating ores which consists in'adding a frothing agent to a stream of pulp, discharging gas into the stream to impart a velocity7 thereto, discharging saidstream upwardly in substantially vertical planes only, permitting said stream to fall back upon itself in contact with a free atmosphere whereby additional air is -enti'ained and the whole mass is agitated, and separating the froth produced thereby.

r..Tlie herein described method of concentrating ores which consists in forcibly impelling a stream'of a mixture of a frothing agent and pulp to rise through and in contact with a body of 'such a mixture to 'a point above the said body, permitting-a portion of the part of the mixture so elevated above the bodyl to fall back thereupon in contact with a free atmosphere forming a froth and separating the froth.

4. The herein described method of concentrating ores which consists in imparting a velocity to a portion of a body of a mixture of pulp and oil, permitting said portion to How through and in contact with the remainder vof the body, deflecting the moving portion upward so that it rises above the remainder of the body and permitting it to fall back upon itself forming a froth.

5. The herein described method of con'- centrating ores which consists in imparting a velocity to a. portion of a body of a mixture of pulp and oil, permitting said portion to flow through and in contact with the remainder of the body, detiecting said moving jecting the resulting stream of said mixture into the body of a similar mixture, elevating a. portion of said body by the energy of said stream and permitting sjaid elevated portion to fall in contact with a free atmosphere back upon said body from a point above the body forming a froth.

7 In an apparatus for concentrating ores,

a chamber, a wall dividing said chamber into compartments, -one of said compartments having a vertically cuiv d' wall, a gas operated inJector extending through said div viding wall for dischargi fr the contents of one compartment into the other and against said curved wall. f

8. In an apparatus for concentrating ores, a compartment having a. vertically curved wall, a gas operated injector for projecting 4a mixture of pulp and oil and a frothing agent .into said compartment and against -s'aid wall to form a froth, and means for separating the froth formed thereby.

9. In an apparatus for concentrating ores, a chamber, a wall extending from the bottom to a point near the top thereof and dividing it into compartments, a gas operated injector extending through said wall for discharging the contents of one compartmentv into the second compartment and a vertically curved throwback plate in said second c oinpartinent against which the -contents ofthe L first compartment is discharged.

10. In an apparatus for y. concentrating ores, a chamber, a wall extending from the bottom to a point neai' the top thereof and -dividing it into compartments, a gas operated injector for discharging the contents of one compartment into the second coinpaitment, a curtain wall extending from the top of the firstlcompartment to a point below theptop of said wall and a vertically curved throwback plate in said second compartm'ent against which the contents of the first compartment is discharged.

In testimony whereof, I have hereunto set my signature this 16th day of April, 1915. HARRY M. DUNN.

l Witnesses:

C. W. MoS-HERRY, T VC. MoSHERRr. 

